I would think that your message would be better focused around hearing and appreciating her than about taking the opportunity to promote your cause with a lot of words about what you want her to think and feel about you. I would have said to the apology text:

Thanks, I understand, and I really appreciate your saying that.

That's it. All the rest seems geared toward telling her something that it will only take time for you to show her. Don't be impatient. You can't request or suggest opportunities to be there for her as a 180, that doesn't work. Show, don't tell. That's what really comes across as genuine change; words are cheap.

Adinva 51, S20, S18
M24 total
6/15/11-12/1/12 From IDLY to H moving out
9/15/15-3/7/17 From negotiating SA to final D at age 50
5/8/17-now: New relationship with an old friend
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Happiness is a warm puppy.